Mining-drill.



f Specification of Letters Patent.

' Patented March 13,1906.

Application filed October 19, 1905. Serial No. 283,474.

.T a/ZZ whom t may concern:

Be it known that l, FRANK LoNsKl, a citivZen of the United States, residing at Plymouth, in the county of Luzerne and State of Pennsylvania, vhave invented new and useful Im rovements in Mining-Drills, of which the fol owing is a specification.

This invention relates to mining-drills.

In the use of mining-drills a very common defect is the loosenin of the fastening device which securesthe dri l bit or bits in the chuck of the drill-stock, so that both the bit or bits and the'fastening device are liable to drop out.

The objectof the present invention is to obviate the defects heretofore incident 4to mining-drills asabove pointed out, and it also-aims to provide an improved chuck for a mining-drill `whereby tools for different purposes can be readily used and held at'different times by the same-fastening- To carry out the objects of the present invention, l provide a mining-drill having an its,

improvedfastenin device for the bit or together with nove means for preventin the fastening device from becoming lost, as lly e set -forth hereinafter. The novel featuresof the invention are recitedin the appended claims.

In the accompanying drawings, Figure l1 is a erspective view showing the center bit in ful lines, the dotted lines representing a small bit which can be used to make the circumferential cut. Fig. 2 is a section al elevation on line 2 2 of Fig. 1; Fig. 3 is a longitudinal sectional elevation on line 3 3 of Fig. 1.

Fi 4 isa detail plan view of the fasteningbo t removed. lFig. 5 is a detail horizontal Asectional elevation, and Figs. 6 and-7 detail views of the fastenin -bolt. K

The stock lis in t e form of a screw and provided with a socket 2'for the reception of 4 the drill rod or stem. The chuck, to which my invention particularly appertain's, is shown at 3 and has a polygonal opening 4extending transversely thereof part way into the chuck' and in communication with a more or less ellipticalaperture 5, opening out on the opposite side of the chuck. The polygonal opening or seat 4 is to receive the head 6 of the fastening-bolt, whose'shank 7 extends vmore or less loosely through the aperture 5` and is providedwith a nut 8, whereby the head '6 is held in the opening 4. This prevents loosening of the bolt when the drill is in PATENT *ottieni y use or at other times. The aperture 5 is enlarged in order that in clamping the bit in the chuck the fastening-bolt will readily adjust itselfto the shank oi' the bit. The opposite sidesv of the head 6 are beveled or more or less undercut at .9 and 10, the side 10 being also beveled transversely `of the head 6. The beveled or undercut portions 9 and 10 are adapted to bear upon the Shanks or tangs of the bits and clamp them in their sockets 11 and 12. The socket 1 1 is of general polygonal shape in cross-section and extends somewhat angularly in relation to the longitudinal axis of the stock 1. The disposition of socket 12 is such that thetipof the drill or bit 13 lies in thelongitudinal axis of the stock, while the inclination of socket 11 .enables a tool such as shown at 14 to bev used with its cutting-point dis osed outside theaxis ofthe stock. A y/dril or bit such as shown at 13 forms the center hole, while such a tool as shown at 14 makes the side or circumferential cut. It is to be understood that various kinds of drills or bits'can be lused and other forms thanl those shown may be' employed. By preference the socket 11 may be square in `crosssection and the socket 12 trian ular; but other cross-sectional shapes coul be used. The' undercut or beveled portion 9 engages the shank of bit 14, and the face 10 engages the shank of bit 13. The shank7 'of the bolt is flattened or grooved on two opposite sides adjacent tothe head l6, so that when the bits are in place their edges engage with these grooves. This prevents vthe bolt from slipping out even if the nut comes 0H, and since this bolt has 4to vbe specially made for this chuck the expense which would be caused by its loss is thus prevented.l

Having thus described my invention, what 9 5 I claim as new, and desire to secure by Letters Patent, is

1. A chuck for mining-drills having a bitsocket, an o ening for the head of the bitfastening bot which intersects the socket, and ana erture-for the shank of the bit-fastening bo t, in combinationwith a fasteningbolt having a headwith a beveled or undercut portion to engage the bit, and which is received in the opening aforesaid and prevented from turning thereby and provided with a shank passing through the aperture and having a narrow portion adjacent to said head, and a nuton said shank. n 2. A chuck for mining-drills having two IIO which said bits engage, and a nut secured to said shank.

FRANK LONSKI.

Witnesses:

T. D. GARMAN, STANLEY ZBoRoWsKI. 

